In many processing and computing systems, magnetic data storage devices, such as disk drives are utilized for storing data. A typical disk drive includes a spindle motor having a rotor for rotating one or more data disks having data storage surfaces, and an actuator for moving a head carrier arm that supports transducer (read/write) heads, radially across the data disks to write data to or read data from concentric data tracks on the data disk.
In the manufacturing of the disk drive, many components with high electrical sensitivities are fabricated and manufactured. Devices such as the heads, sliders, etc., have electrical sensitivities to electromagnetic interferences or electrostatic discharge that requires the manufacturing environment worker to exercise great caution in the manufacturing of these components. Components such as suspensions comprise of conductive materials which tend to have conductive traces that are typically supported by insulative materials to help reduce the potential for electrostatic discharge or electromagnetic interference. When the suspension or similar components come into contact with each other.
Several manufacturing techniques have been adopted to reduce the amount of electrostatic discharge that occurs as the hard disk drive components are manufactured and assembled in the manufacturing environment. Some of these techniques include requiring assembly workers to wear electrostatic straps when they move the hard disk drive components about the manufacturing environment. The wrist strap is connected to a suitable ground point by means of a conducting cable. This way, a path is provided by which any static charge in the body of the wearer is conveyed to ground and thereby harmlessly dissipated. It is only necessary for the worker to wear a grounding strap on one wrist to enable him to safely handle electronic devices with either hand since the ground point serve to dissipate the charge from the entire body.
The problem with the use of wrist straps is that when a user is disconnected from the ground point as a result of the user being interrupted from their work and leaving the work-area, the user may or may not reconnect themselves upon return to the work-area. This is more so the case in a fast paced component assembly environment such as in a hard disk drive fabrication environment.
Some current solutions provide the use of wrist strap monitoring devices to monitor when the user is disconnected from ground. These monitors use localized alarm systems which only notify the user of their being disconnected from ground.
However, the problem with these current monitors is that the user tend to ignore or neglect the monitor alarms for several reasons including production downtime during the replacement of the wriststraps, production downtime during the replacement or repair of the monitor if the monitor itself is defective. Other problems may include damaged wriststrap jacks or terminals which may not alarm even when a user is detached from the monitor, wrong or improper connection by the user, and users forgetting to plug in their wrist straps.
Therefore, what is need is a flexible way of component fabrication and manufacturing that permits static charges to be controllably dissipated from the materials used in the construction of these components such that the potential damage from electrostatic discharge or electromagnetic interference to electric components connected to such components is reduced and an improved way of monitoring the wrist strap by providing a wider visibility of the alarm indicators to a larger group of operators in the assembly environment.